The present invention relates generally to golf equipment and, in particular, to a golf club head.
An important factor governing the distance and accuracy of a golfer's drive is the amount of energy transferred from the golf club head to a golf ball when it impacts the golf ball. Ideally, the point of impact on the face of the golf club head is below the center of gravity of the golf club head and the point of impact on the golf ball is below the center of gravity of the golf ball. In addition, the theoretical plane containing the impact point on the golf club head, the center of gravity of the golf club head, and the center of gravity of the golf ball should be in alignment with the intended travel path of the golf ball. When these conditions are met, the golf club head is properly aligned and produces maximum face response characteristics.
To help golfers achieve proper alignment, golf club manufacturers have concentrated a relatively large mass of the golf club head in its sole. This configuration has made it easier for a golfer to place the center of gravity of the golf club head below the center of gravity of the golf ball; however it is still difficult for a golfer to achieve perfect alignment. For example, a golfer may have the club head square immediately prior to impact, but the actual point of impact with the club head may be shifted from the desired point on the club head to either the heel end or the toe end. This results in improper alignment because the club head becomes twisted to an out of square position and results in less than the maximum amount of energy being transferred to the golf ball. The terms twisting, twisted, or gyration are used here to define a rotation of the club head at the time of impact about an axis which passes through the center of gravity of the club head and is parallel to the axis of the golf club shaft. To dampen or reduce the effects caused by twisting of the club head, golf club manufacturers have placed relatively large concentrations of mass in the heel and toe of the club head to increase the moment of inertia and thereby maximize the energy transfer from the club head to the golf ball. Although these techniques have improved the ability of the golfer to increase the consistency with which they properly align the golf club, slight misalignment of the golf club head results in less than optimum face response characteristics.
In addition, an important criterion in selecting a golf club is the “feel” of the club when the club face contacts the golf ball. One of the factors contributing to the “feel” of the golf club is the stiffness of the club face. Because no two golfers are the same, the “feel” of the club preferred by one golfer might be different from that preferred by another golfer. However, golf club manufacturers have been constrained to manufacture sets of golf clubs with a fairly uniform stiffness. Thus, golfers have been limited in their choices of clubs with respect to the stiffness of the golf club.
Accordingly, what is needed is a golf club head, a method for manufacturing the golf club head, and a method for tuning the golf club head that permits adjusting the stiffness and the face response characteristics of the golf club head.